DE9211664U1 - Analog thermocouple amplifier with digital linearization - Google Patents

Analog thermocouple amplifier with digital linearization

Info

Publication number
DE9211664U1
DE9211664U1 DE9211664U DE9211664U DE9211664U1 DE 9211664 U1 DE9211664 U1 DE 9211664U1 DE 9211664 U DE9211664 U DE 9211664U DE 9211664 U DE9211664 U DE 9211664U DE 9211664 U1 DE9211664 U1 DE 9211664U1
Authority
DE
Germany
Prior art keywords
amplifier
signal
thermocouple
linearization
difference
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
DE9211664U
Other languages
German (de)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gepa 8000 Muenchen De GmbH
Original Assignee
Gepa 8000 Muenchen De GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from DE9114346U external-priority patent/DE9114346U1/en
Application filed by Gepa 8000 Muenchen De GmbH filed Critical Gepa 8000 Muenchen De GmbH
Priority to DE9211664U priority Critical patent/DE9211664U1/en
Publication of DE9211664U1 publication Critical patent/DE9211664U1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D3/00—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups
    • G01D3/02—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups with provision for altering or correcting the law of variation
    • G01D3/022—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups with provision for altering or correcting the law of variation having an ideal characteristic, map or correction data stored in a digital memory
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
    • G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
    • G01K7/02—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using thermoelectric elements, e.g. thermocouples
    • G01K7/14—Arrangements for modifying the output characteristic, e.g. linearising

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Technology Law (AREA)
  • Indication And Recording Devices For Special Purposes And Tariff Metering Devices (AREA)

Description

1. Analoge Korrektur1. Analogue correction

Vorteile : Relativ einfacher Aufbau, kostengünstigAdvantages: Relatively simple construction, cost-effective

Nachteile: selbst temperaturabhängig, Abweichungen von der Sollkorrekturkurve unvermeidbar, nur punktuell im Übertragungsbereich Übereinstimmung von SoIlu. Ist-Wert erreichbar.Disadvantages: temperature dependent, deviations from the target correction curve are unavoidable, agreement between target and actual value can only be achieved at certain points in the transmission range.

Eine hohe Genauigkeit, sowie eine Bereichsumschaltung nach Element-Typ oder/und Temperaturgrenzen ist nur mit extrem aufwendiger
Schaltungstechnik möglich. (Unter Beibehaltung der nachteiligen eigenen Temperaturabhängigkeit! )A high level of accuracy, as well as a range switching according to element type and/or temperature limits, is only possible with extremely complex
Circuit technology possible. (While retaining the disadvantageous temperature dependence!)

2. Digitale Korrektur2. Digital correction

Vorteile : genaue Abbildung der Korrekturtabelle im
digitalen Speicher. Es ergibt sich je
nach Wandlungsbreite eine hohe Genauigkeit.
Realisierung von unterschiedlichen
Sensorelementen und Meßbereichen möglich,
selbst temperaturunabhängigAdvantages: exact representation of the correction table in
digital memory. Depending on the
high accuracy depending on the conversion range.
Realization of different
Sensor elements and measuring ranges possible,
even temperature independent

Nachteile: Mind.l2bit Wortbreite zur Digitalisierung des
Meßsignales für hohe Genauigkeit erforderlich.
Damit hoher Kostenaufwand gegeben. ( Filter,
12bit-A/D-Wandler, Speicher, D/A-Wandler,
Filter...)Disadvantages: At least 12bit word width for digitizing the
Measuring signal required for high accuracy.
This results in high costs (filters,
12bit A/D converter, memory, D/A converter,
Filter...)

Die erfindunsgemäße Linearisierung ist nun so ausgebildet, daß zur Korrektur der Kennlinie des Thermoelementes nur der Teil digitalisiert wird, der die Differenz zwischen Soll- und Istwert des Meßsignales darstellt. Es ergeben sich damit zwei Signalwege:The linearization according to the invention is designed in such a way that to correct the characteristic curve of the thermocouple, only the part that represents the difference between the target and actual value of the measurement signal is digitized. This results in two signal paths:

GEPAmbH, München 2/2 26.08.92GEPAmbH, Munich 2/2 26.08.92

-Linearer Teil (unkorrigiert)
-digitalisierter Differenzanteil-Linear part (uncorrected)
-digitized difference component

Der Differenzteil wird mit Hilfe einer Korrekturtabelle aus
einem Halbleiterspeicher, digital korrigiert und durch Summation am Ausgang mit dem linearen Teil zusammengefaßt. Diese Summe ergibt das entgültige linearisierte Meßsignal.The difference part is calculated using a correction table from
a semiconductor memory, digitally corrected and summed with the linear part at the output. This sum results in the final linearized measurement signal.

Da das gebildete Differenzsignal nur einen Bruchteil (<6%) des gesamten Meßsignalpegels darstellt, reicht hier eine A/D-D/AWandlung mit wesentlich geringerer Auflösung (z.B. 8bit) zur genauen Abbildung des Korrektursignales aus. Die Genauigkeit des Gesamtsignales kann mit wesentlich höher auflösenden Systemen (z.B. 12bit) gleichgesetzt werden.Since the difference signal formed represents only a fraction (<6%) of the total measurement signal level, an A/D-D/A conversion with a much lower resolution (e.g. 8 bit) is sufficient to accurately represent the correction signal. The accuracy of the overall signal can be equated with systems with a much higher resolution (e.g. 12 bit).

Vorteile : Vermeidung des hohen Aufwandes (materiell, wieAdvantages: Avoidance of high expenditure (material, such as

schaltungstechnisch) von reinen Digitalsystemen unter Beibehaltung der hohen Genauigkeit und
Flexibilität digitaler Lösungen.
Vermeidung der Temperaturabhängigkeit analoger Lösungen.circuitry) of pure digital systems while maintaining high accuracy and
Flexibility of digital solutions.
Avoiding the temperature dependence of analog solutions.

Die Erfindung ist weiterhin so ausgebildet, daß die Linearisierungstabellen im Verstärker auf einen EEPROM gespeichert sind, der sich in der Schaltung jederzeit mit willkürlichen Linearisierungstabellen programmieren läßt.
Somit ergibt sich ein jedem Temperatursensor und jedem Messbereich softwaremäßig anpaßbarer Temperaturmessverstärker.The invention is further designed such that the linearization tables in the amplifier are stored on an EEPROM, which can be programmed in the circuit at any time with arbitrary linearization tables.
This results in a temperature measuring amplifier that can be adapted to any temperature sensor and any measuring range using software.

Die Funktionsweise der dargelegten Lösung ist zusätzlich im beigefügten Blockschaltplan ersichtlich.The functionality of the solution presented is also shown in the attached block diagram.

Claims (2)

GEPAmbH, München 1/1 26.08.92 Schutzanspruch Analoger Thermoelement-Meßverstärker mit digitaler LinearisierungGEPAmbH, Munich 1/1 26.08.92 Claim for protection Analog thermocouple measuring amplifier with digital linearization 1) Thermoelement-Verstärker, dadurch gekennzeichnet, daß zur Linearisierung der Kennlinie des Thermoelementes nur der Teil digitalisiert wird, der die Differenz zwischen SoIl- und Istwert des Messwertes darstellt. Es ergeben sich somit zwei Wege des Meßsignales:1) Thermocouple amplifier, characterized in that in order to linearize the characteristic curve of the thermocouple, only the part that represents the difference between the target and actual value of the measured value is digitized. This results in two paths for the measuring signal: -Linearer Teil (unkorrigiert)
-digitalisierter Differenzanteil-Linear part (uncorrected)
-digitized difference component Der Differenzteil wird durch die Verstärkerschaltung mit Hilfe einer Korrekturtabelle aus einem Halbleiterspeicher digital korrigiert und durch Summation am Ausgang mit dem linearen Teil zusammengefaßt. Diese Summe ergibt das endgültige, linearisierte Meßsignal.The differential part is digitally corrected by the amplifier circuit using a correction table from a semiconductor memory and combined with the linear part by summation at the output. This sum produces the final, linearized measurement signal. Da das gebildete Differenzsignal nur einen Bruchteil (<6%) des gesamten Meßsignalpegels darstellt, reicht hier eine A/D-D/A-Wandlung mit wesentlich geringerer Auflösung (z.B. 8bit) zur genauen Abbildung des Korrektursignales aus. Die Genauigkeit des Gesamtsignales kann mit wesentlich höher auflösenden Systemen (z.B. 12bit) gleichgesetzt werden.Since the difference signal formed represents only a fraction (<6%) of the total measurement signal level, an A/D-D/A conversion with a much lower resolution (e.g. 8 bit) is sufficient to accurately represent the correction signal. The accuracy of the overall signal can be equated with much higher resolution systems (e.g. 12 bit). 2) Verstärker nach Anspruch 1, gekennzeichnet dadurch, daß die Linearisierungstabellen im Verstärker auf einen EEPROM gespeichert sind, der sich in der Schaltung jederzeit mit willkürlichen Linearisierungstabellen programmieren läßt.2) Amplifier according to claim 1, characterized in that the linearization tables in the amplifier are stored on an EEPROM which can be programmed in the circuit at any time with arbitrary linearization tables.
DE9211664U 1991-11-18 1992-08-29 Analog thermocouple amplifier with digital linearization Expired - Lifetime DE9211664U1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE9211664U DE9211664U1 (en) 1991-11-18 1992-08-29 Analog thermocouple amplifier with digital linearization

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE9114346U DE9114346U1 (en) 1991-11-18 1991-11-18 DC voltage and carrier frequency measuring amplifier
DE9211664U DE9211664U1 (en) 1991-11-18 1992-08-29 Analog thermocouple amplifier with digital linearization

Publications (1)

Publication Number Publication Date
DE9211664U1 true DE9211664U1 (en) 1992-12-10

Family

ID=25958861

Family Applications (1)

Application Number Title Priority Date Filing Date
DE9211664U Expired - Lifetime DE9211664U1 (en) 1991-11-18 1992-08-29 Analog thermocouple amplifier with digital linearization

Country Status (1)

Country Link
DE (1) DE9211664U1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1008153C2 (en) * 1997-01-31 1998-08-18 Omega Engineering Thermoelectric object and method.
EP0947808A1 (en) * 1998-03-31 1999-10-06 Sanyo Electric Co. Ltd Method for calibrating a sensor
DE10158836A1 (en) * 2001-11-30 2003-06-18 Infineon Technologies Ag Method for sensor system calibration in which sensor system can be operated in normal measurement mode or calibration mode, when its sensitivity and resolution are much higher than in normal operating mode
DE10236722A1 (en) * 2002-08-06 2004-02-26 Carsten Schippmann Analogue measurement coverter for linearization of measurement signals or generation of non-linear transfer characteristic curves for use with physical value measurement sensors comprises linearization units and offset generator
DE19846461B4 (en) * 1997-10-08 2006-05-11 Hitachi, Ltd. Sensoreinstellschaltung
EP1669732A1 (en) * 2004-12-07 2006-06-14 Isabellenhütte Heusler GmbH &amp; Co.KG Temperature measuring system and method
WO2011157832A3 (en) * 2010-06-18 2012-08-23 Phoenix Contact Gmbh & Co. Kg Measuring transducer having two transmission channels

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2762908A1 (en) * 1997-01-31 1998-11-06 Omega Engineering METHOD AND DEVICE FOR OBTAINING A COMPENSATED ANALOG SIGNAL FROM AN OUTPUT SIGNAL OF A THERMOELECTRIC DEVICE
NL1008153C2 (en) * 1997-01-31 1998-08-18 Omega Engineering Thermoelectric object and method.
DE19846461B4 (en) * 1997-10-08 2006-05-11 Hitachi, Ltd. Sensoreinstellschaltung
EP0947808A1 (en) * 1998-03-31 1999-10-06 Sanyo Electric Co. Ltd Method for calibrating a sensor
US6082122A (en) * 1998-03-31 2000-07-04 Sanyo Electric Co., Ltd. Method for calibrating a measured value of detecting means
DE10158836B4 (en) * 2001-11-30 2007-06-06 Infineon Technologies Ag Method and device for calibrating a sensor system
DE10158836A1 (en) * 2001-11-30 2003-06-18 Infineon Technologies Ag Method for sensor system calibration in which sensor system can be operated in normal measurement mode or calibration mode, when its sensitivity and resolution are much higher than in normal operating mode
DE10236722B4 (en) * 2002-08-06 2005-12-29 Schippmann, Carsten, Dipl.-Ing. Analogue transducer for linearization and generation of non-linear transfer characteristics
DE10236722A1 (en) * 2002-08-06 2004-02-26 Carsten Schippmann Analogue measurement coverter for linearization of measurement signals or generation of non-linear transfer characteristic curves for use with physical value measurement sensors comprises linearization units and offset generator
EP1669732A1 (en) * 2004-12-07 2006-06-14 Isabellenhütte Heusler GmbH &amp; Co.KG Temperature measuring system and method
WO2011157832A3 (en) * 2010-06-18 2012-08-23 Phoenix Contact Gmbh & Co. Kg Measuring transducer having two transmission channels
CN102947684A (en) * 2010-06-18 2013-02-27 菲尼克斯电气有限两合公司 Measuring transducer having two transmission channels
CN102947684B (en) * 2010-06-18 2015-07-22 菲尼克斯电气有限两合公司 Measuring transducer having two transmission channels
US9506810B2 (en) 2010-06-18 2016-11-29 Phoenix Contact Gmbh & Co. Kg Measuring transducer having two transmission channels

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